Engineering Board Exam Reviewer · Linear First-Order Differential Equations · hard
Solve xdy/dx+y=x2 for x>0.
- y=x2/3+C/x
- y=x2/3+C
- y=x3/3+C/x
- y=x/3+C/x
Answer
A. y=x2/3+C/x
Solution
Rewrite as dy/dx+y/x=x. The integrating factor is =x: (xy)'=x2 xy=x3/3+C y=x2/3+C/x.